<?php
/*********************************************
  CPG Dragonfly™ CMS
  ********************************************
  Copyright © 2004 - 2007 by CPG-Nuke Dev Team
  http://dragonflycms.org

  Dragonfly is released under the terms and conditions
  of the GNU GPL version 2 or any later version

  $Source$
  $Revision$
  $Author$
  $Date$
**********************************************/
/*
  Nathan Codding - Original version design and implementation
  Crimsonbane - Initial caching proposal and work
  psoTFX - Completion of file caching, decompilation routines and implementation of
  conditionals/keywords and associated changes

  The interface was inspired by PHPLib templates, and the template file (formats are
  quite similar)

  The keyword/conditional implementation is currently based on sections of code from
  the Smarty templating engine (c) 2001 ispi of Lincoln, Inc. which is released
  (on its own and in whole) under the LGPL. Section 3 of the LGPL states that any code
  derived from an LGPL application may be relicenced under the GPL, this applies
  to this source

  DEFINE directive inspired by a request by Cyberalien
*/

class tpl_encode
{

	// The all seeing all doing compile method. Parts are inspired by or directly
	// from Smarty
	public function compile($code, $no_echo = false, $echo_var = '')
	{
		// Remove any "loose" php ... we want to give admins the ability
		// to switch on/off PHP for a given template. Allowing unchecked
		// php is a no-no. There is a potential issue here in that non-php
		// content may be removed ... however designers should use entities
		// if they wish to display < and >
		$match_php_tags = array('#\<\?php .*?\?\>#is', '#\<\script language="php"\>.*?\<\/script\>#is', '#\<\?.*?\?\>#s', '#\<%.*?%\>#s');
		$code = preg_replace($match_php_tags, '', $code);

		// Pull out all block/statement level elements and seperate plain text
		preg_match_all('#<!-- PHP -->(.*?)<!-- ENDPHP -->#s', $code, $matches);
		$php_blocks = $matches[1];
		$code = preg_replace('#<!-- PHP -->(.*?)<!-- ENDPHP -->#s', '<!-- PHP -->', $code);

		preg_match_all('#<!-- INCLUDE ([a-zA-Z0-9\_\-\+\.\/{}]+?) -->#', $code, $matches);
		$include_blocks = $matches[1];
		$code = preg_replace('#<!-- INCLUDE ([a-zA-Z0-9\_\-\+\.\/{}]+?) -->#', '<!-- INCLUDE -->', $code);

		preg_match_all('#<!-- INCLUDEPHP ([a-zA-Z0-9\_\-\+\.\\\\\/]+?) -->#', $code, $matches);
		$includephp_blocks = $matches[1];
		$code = preg_replace('#<!-- INCLUDEPHP ([a-zA-Z0-9\_\-\+\.\/]+?) -->#', '<!-- INCLUDEPHP -->', $code);

		preg_match_all('#<!-- (.*?) (.*?)?[ ]?-->#s', $code, $blocks);
		$text_blocks = preg_split('#<!-- (.*?) (.*?)?[ ]?-->#s', $code);
		if ($text_blocks[count($text_blocks)-1] == '') {
			unset($text_blocks[count($text_blocks)-1]);
		}
		for($i = 0, $c = count($text_blocks); $i < $c; ++$i) {
			self::compile_var_tags($text_blocks[$i]);
		}

		$compile_blocks = array();
		$block_else_level = array();
		$this->block_names = array();
		for ($i = 0, $c = count($text_blocks); $i < $c; ++$i)
		{
			if (isset($blocks[1][$i]))
			switch ($blocks[1][$i])
			{
				case 'BEGIN':
					$block_else_level[] = false;
					$compile_blocks[] = '<?php ' . self::compile_tag_block($blocks[2][$i]) . ' ?>';
					break;

				case 'BEGINELSE':
					$block_else_level[count($block_else_level) - 1] = true;
					$compile_blocks[] = '<?php }} else { ?>';
					break;

				case 'END':
					array_pop($this->block_names);
					$compile_blocks[] = '<?php ' . ((array_pop($block_else_level)) ? '}' : '}}') . ' ?>';
					break;

				case 'IF':
					$compile_blocks[] = '<?php ' . self::compile_tag_if($blocks[2][$i], false) . ' ?>';
					break;

				case 'ELSE':
					$compile_blocks[] = '<?php } else { ?>';
					break;

				case 'ELSEIF':
					$compile_blocks[] = '<?php ' . self::compile_tag_if($blocks[2][$i], true) . ' ?>';
					break;

				case 'ENDIF':
					$compile_blocks[] = '<?php } ?>';
					break;

				case 'DEFINE':
					$compile_blocks[] = '<?php ' . self::compile_tag_define($blocks[2][$i], true) . ' ?>';
					break;

				case 'UNDEFINE':
					$compile_blocks[] = '<?php ' . self::compile_tag_define($blocks[2][$i], false) . ' ?>';
					break;

				case 'INCLUDE':
					$temp = array_shift($include_blocks);
					$compile_blocks[] = '<?php $this->_tpl_include(\''.$temp."'); ?>";
					$this->_tpl_include($temp, false);
					break;

				case 'INCLUDEPHP':
					/*	$compile_blocks[] = "<?php include('".$this->root.'/'.array_shift($includephp_blocks))."'); ?>"; */
					break;

				case 'PHP':
					$compile_blocks[] = '<?php '.array_shift($php_blocks).' ?>';
					break;

				default:
					self::compile_var_tags($blocks[0][$i]);
					$trim_check = trim($blocks[0][$i]);
					$compile_blocks[] = (!$no_echo) ? ((!empty($trim_check)) ? $blocks[0][$i] : '') : ((!empty($trim_check)) ? $blocks[0][$i] : '');
					break;
			}
		}
		$template_php = '';
		for ($i = 0, $c = count($text_blocks); $i < $c; ++$i) {
			$trim_check_text = trim($text_blocks[$i]);
			$trim_check_block = isset($compile_blocks[$i]) ? trim($compile_blocks[$i]) : '';
			$template_php .= (!$no_echo) ? ((!empty($trim_check_text)) ? $text_blocks[$i] : '') . ((!empty($compile_blocks[$i])) ? $compile_blocks[$i] : '') : ((!empty($trim_check_text)) ? $text_blocks[$i] : '') . ((!empty($compile_blocks[$i])) ? $compile_blocks[$i] : '');
		}
		// There will be a number of occassions where we switch into and out of
		// PHP mode instantaneously. Rather than "burden" the parser with this
		// we'll strip out such occurences, minimising such switching
		$template_php = str_replace(' ?><?php ', '', $template_php);
		return  (!$no_echo) ? $template_php : "\$$echo_var .= '" . $template_php . "'";
	}

	private function compile_var_tags(&$text_blocks)
	{
		// change template varrefs into PHP varrefs
		$varrefs = array();
		// This one will handle varrefs WITH namespaces
		preg_match_all('#\{(([a-z0-9\-_\[\]\'\"]+?\.)+?)(\$)?([A-Z0-9\-_]+?)\}#', $text_blocks, $varrefs);
		for ($i=0, $c=count($varrefs[1]); $i<$c; ++$i) {
			$namespace = $varrefs[1][$i];
			$varname = $varrefs[4][$i];
			$new = self::generate_block_varref($namespace, $varname, true, $varrefs[3][$i]);
			$text_blocks = str_replace($varrefs[0][$i], $new, $text_blocks);
		}
		# This will handle URL::index()
		$text_blocks = preg_replace('#U_\(([a-z0-9\-_&;=]*?)(\,[0-1]{1}(\,[0-1]{1})?)?\)#is', '<?php echo URL::index(\'\\1\'\\2); ?>', $text_blocks);
		# This will handle URL::admin()
		/*$text_blocks = preg_replace('#UADMIN_\(([a-z0-9\-_&;=]*?)\<\?php echo (.*?); \?>\)#i', '<?php echo URL::admin(\'\\1\'.\\2); ?>', $text_blocks);*/
		$text_blocks = preg_replace('#UADMIN_\(([a-z0-9\-_&;=]*?)(\,[0-1]{1})?\)#is', '<?php echo URL::admin(\'\\1\'\\2); ?>', $text_blocks);
		# This will handle language strings
		$text_blocks = preg_replace('#L?_\(([a-z0-9\-_]*?)\)#is', '<?php echo (isset($lang[\'$1\']) ? $lang[\'$1\'] : _$1); ?>', $text_blocks);
		// This will handle the remaining root-level varrefs
		$text_blocks = preg_replace('#{([a-z0-9\-_]*?)}#is', "<?php echo \$this->_tpldata['.'][0]['\\1']; ?>", $text_blocks);
		$text_blocks = preg_replace('#{\$([a-z0-9\-_]*?)}#is', "<?php echo \$this->_tpldata['DEFINE']['.']['\\1']; ?>", $text_blocks);
		return;
	}

	private function compile_tag_block($tag_args)
	{
		// Allow for control of looping (indexes start from zero):
		// foo(2)	: Will start the loop on the 3rd entry
		// foo(-2)   : Will start the loop two entries from the end
		// foo(3,4)  : Will start the loop on the fourth entry and end it on the fourth
		// foo(3,-4) : Will start the loop on the fourth entry and end it four from last
		if (preg_match('#^(.*?)\(([\-0-9]+)(,([\-0-9]+))?\)$#', $tag_args, $match)) {
			$tag_args = $match[1];
			$loop_start = ($match[2] < 0) ? '$_' . $tag_args . '_count ' . ($match[2] - 1) : $match[2];
			$loop_end = ($match[4]) ? (($match[4] < 0) ? '$_' . $tag_args . '_count ' . $match[4] : ($match[4] + 1)) : '$_' . $tag_args . '_count';
		} else {
			$loop_start = 0;
			$loop_end = '$_' . $tag_args . '_count';
		}
		$tag_template_php = '';
		array_push($this->block_names, $tag_args);
		if (count($this->block_names) < 2) {
			// Block is not nested.
			$tag_template_php = '$_' . $tag_args . "_count = (isset(\$this->_tpldata['$tag_args'])) ?  count(\$this->_tpldata['$tag_args']) : 0;";
		} else {
			// This block is nested.
			// Generate a namespace string for this block.
			$namespace = implode('.', $this->block_names);
			// Get a reference to the data array for this block that depends on the
			// current indices of all parent blocks.
			$varref = self::generate_block_data_ref($namespace, false, false);
			// Create the for loop code to iterate over this block.
			$tag_template_php = '$_' . $tag_args . '_count = (isset(' . $varref . ')) ? count(' . $varref . ') : 0;';
		}
		$tag_template_php .= 'if ($_' . $tag_args . '_count) {';
		$tag_template_php .= 'for ($this->_' . $tag_args . '_i = ' . $loop_start . '; $this->_' . $tag_args . '_i < ' . $loop_end . '; $this->_' . $tag_args . '_i++){';
		return $tag_template_php;
	}

	//
	// Compile IF tags - much of this is from Smarty with
	// some adaptions for our block level methods
	//
	private function compile_tag_if($tag_args, $elseif)
	{
		/* Tokenize args for 'if' tag. */
		preg_match_all('/(?:
						 "[^"\\\\]*(?:\\\\.[^"\\\\]*)*"	 |
						 \'[^\'\\\\]*(?:\\\\.[^\'\\\\]*)*\' |
						 [(),]							  |
						 [^\s(),]+)/x', $tag_args, $match);
		$tokens = $match[0];
		$is_arg_stack = array();
		for ($i = 0, $c = count($tokens); $i < $c; ++$i) {
			$token = &$tokens[$i];
			switch ($token)
			{
				case '!':
				case '%':
				case '!==':
				case '==':
				case '===':
				case '>':
				case '<':
				case '!=':
				case '<>':
				case '<<':
				case '>>':
				case '<=':
				case '>=':
				case '&&':
				case '||':
				case '|':
				case '^':
				case '&':
				case '~':
				case ')':
				case ',':
				case '+':
				case '-':
				case '*':
				case '/':
				case '@':
					break;

				case 'eq':
					$token = '==';
					break;

				case 'ne':
				case 'neq':
					$token = '!=';
					break;

				case 'lt':
					$token = '<';
					break;

				case 'le':
				case 'lte':
					$token = '<=';
					break;

				case 'gt':
					$token = '>';
					break;

				case 'ge':
				case 'gte':
					$token = '>=';
					break;

				case 'and':
					$token = '&&';
					break;

				case 'or':
					$token = '||';
					break;

				case 'not':
					$token = '!';
					break;

				case 'mod':
					$token = '%';
					break;

				case '(':
					array_push($is_arg_stack, $i);
					break;

				case 'is':
					$is_arg_start = ($tokens[$i-1] == ')') ? array_pop($is_arg_stack) : $i-1;
					$is_arg	   = implode('	', array_slice($tokens, $is_arg_start, $i - $is_arg_start));
					$new_tokens   = self::parse_is_expr($is_arg, array_slice($tokens, $i+1));
					array_splice($tokens, $is_arg_start, count($tokens), $new_tokens);
					$i = $is_arg_start;

				default:
					if (preg_match('#^(([a-z0-9\-_]+?\.)+?)?(\$)?([A-Z]+[A-Z0-9\-_]+)$#s', $token, $varrefs)) {
						$token = (!empty($varrefs[1])) ? self::generate_block_data_ref(substr($varrefs[1], 0, -1), true, $varrefs[3]) . '[\'' . $varrefs[4] . '\']' : (($varrefs[3]) ? '$this->_tpldata[\'DEFINE\'][\'.\'][\'' . $varrefs[4] . '\']' : '$this->_tpldata[\'.\'][0][\'' . $varrefs[4] . '\']');
					}
					break;
			}
		}
		return (($elseif) ? '} elseif (' : 'if (') . (implode(' ', $tokens) . ') { ');
	}

	private function compile_tag_define($tag_args, $option)
	{
		preg_match('#^(([a-z0-9\-_]+?\.)+?)?\$([A-Z][A-Z0-9_\-]*?) = (\'?)(.*?)(\'?)$#', $tag_args, $match);
		if (empty($match[3]) || empty($match[5])) {
			trigger_error("'$tag_args' is no proper &lt;!-- DEFINE --&gt; format.", E_USER_WARNING);
			return;
		}

		// Are we a string?
		if ($match[4] && $match[6]) {
			// Can't use addslashes as we don't know what value has magic_quotes_sybase.
			$match[5] = "'" . addcslashes(str_replace(array('\\\'', '\\\\'), array('\'', '\\'), $match[5]), "\0..\37\177\\\"'") . "'"; //"
		} else {
			preg_match('#(true|false|\.)#i', $match[5], $type);

			switch (strtolower($type[1])) {
				case 'true':
				case 'false':
					$match[5] = strtoupper($match[5]);
					break;
				case '.':
					$match[5] = doubleval($match[5]);
					break;
				default:
					$match[5] = intval($match[5]);
					break;
			}
		}

		if ($option) {
			return (($match[1]) ? self::generate_block_data_ref(substr($match[1], 0, -1), true, true) . '[\'' . $match[3] . '\']' : '$this->_tpldata[\'DEFINE\'][\'.\'][\'' . $match[3] . '\']') . ' = ' . $match[5] . ';';
		} else {
			return 'unset(' . (($match[1]) ? self::generate_block_data_ref(substr($match[1], 0, -1), true, true) . '[\'' . $match[3] . '\']' : '$this->_tpldata[\'DEFINE\'][\'.\'][\'' . $match[3] . '\']') . ');';
		}
	}

	// This is from Smarty
	private function parse_is_expr($is_arg, $tokens) {
		$expr_end =	0;
		$negate_expr = false;
		if (($first_token = array_shift($tokens)) == 'not') {
			$negate_expr = true;
			$expr_type = array_shift($tokens);
		} else {
			$expr_type = $first_token;
		}
		switch ($expr_type)
		{
			case 'even':
				if ($tokens[$expr_end] == 'by') {
					++$expr_end;
					$expr_arg =	$tokens[$expr_end++];
					$expr =	"!(($is_arg	/ $expr_arg) % $expr_arg)";
				} else {
					$expr =	"!($is_arg % 2)";
				}
				break;

			case 'odd':
				if ($tokens[$expr_end] == 'by') {
					++$expr_end;
					$expr_arg =	$tokens[$expr_end++];
					$expr =	"(($is_arg / $expr_arg)	% $expr_arg)";
				} else {
					$expr =	"($is_arg %	2)";
				}
				break;

			case 'div':
				if ($tokens[$expr_end] == 'by') {
					++$expr_end;
					$expr_arg =	$tokens[$expr_end++];
					$expr =	"!($is_arg % $expr_arg)";
				}
				break;

			default:
				break;
		}
		if ($negate_expr) { $expr =	"!($expr)"; }
		array_splice($tokens, 0, $expr_end,	$expr);
		return $tokens;
	}

	/**
	 * Generates a reference to the given variable inside the given (possibly nested)
	 * block namespace. This is a string of the form:
	 * ' . $this->_tpldata['parent'][$_parent_i]['$child1'][$_child1_i]['$child2'][$_child2_i]...['varname'] . '
	 * It's ready to be inserted into an "echo" line in one of the templates.
	 * NOTE: expects a trailing "." on the namespace.
	 */
	private function generate_block_varref($namespace, $varname, $echo = true, $defop = false)
	{
		# Strip the trailing period.
		$namespace = substr($namespace, 0, strlen($namespace) - 1);
		# Get a reference to the data block for this namespace.
		$varref = self::generate_block_data_ref($namespace, true, $defop);
		# Append the variable reference.
		$varref .= "['$varname']";
		return (($echo) ? "<?php echo $varref; ?>" : $varref);
	}

	/**
	 * Generates a reference to the array of data values for the given
	 * (possibly nested) block namespace. This is a string of the form:
	 * $this->_tpldata['parent'][$_parent_i]['$child1'][$_child1_i]['$child2'][$_child2_i]...['$childN']
	 *
	 * If $include_last_iterator is true, then [$_childN_i] will be appended to the form shown above.
	 * NOTE: does not expect a trailing "." on the blockname.
	 */
	private function generate_block_data_ref($blockname, $include_last_iterator, $defop)
	{
		# Get an array of the blocks involved.
		$blocks = explode('.', $blockname);
		$blockcount = count($blocks) - 1;
		$varref = '$this->_tpldata' . (($defop) ? '[\'DEFINE\']' : '');
		# Build up the string with everything but the last child.
		for ($i = 0; $i < $blockcount; ++$i) {
			$varref .= "['" . $blocks[$i] . "'][\$this->_" . $blocks[$i] . '_i]';
		}
		# Add the block reference for the last child.
		$varref .= "['" . $blocks[$blockcount] . "']";
		# Add the iterator for the last child if requried.
		if ($include_last_iterator) { $varref .= '[$this->_' . $blocks[$blockcount] . '_i]'; }
		return $varref;
	}

	public function compile_write(&$handle, &$data)
	{
		$filename = str_replace('/', '#', $this->filename[$handle]);
		$filename = $this->cachepath.$filename.'.inc';
		file_write(BASEDIR.$filename, $data);
		return;
	}

}
